JPH02141009A - Sampling phase detector - Google Patents

Abstract

PURPOSE:To form a sampling phase detector as a monolithic integrated circuit on a gallium-arsenide substrate by switching a field-effect transistor by using amplitude limit circuits, delay circuit, and an AND gate. CONSTITUTION:Pulses having a narrow and sharp width are produced from low-frequency sine wave signals by means of amplitude limit circuits A and B, delay circuits C and D, and AND gate E and a field-effect transistor 14 is switched for sampling microwaves by using the pulses as the control signal. Therefore, it becomes unnecessary to use any transformer and step recover diode, and since the microwaves are sampled with reference signals of nanowatts, the whole circuit of this detector can be formed as a monolithic integrated circuit on a gallium-arsenide substrate. Thus a phase synchronizing oscillation circuit can be miniaturized.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a sampling phase detector used in a microwave imperial phase-locked oscillator, and enables the monolithic integrated circuit on a gallium arsenide substrate. Regarding circuit configuration.

[Conventional technology]

A conventional sampling phase detector is shown in FIG.

That is, the low frequency reference signal applied between terminals 1 and 2 is passed through an 8ft transformer to a narrow node synchronized with the reference signal by a pre-recovery diode 3. converted to Luz. Using this as a control signal, Schottky barrier diode 4#5 is operated to switch, the microwave input from terminal 6 is sampled, and a voltage corresponding to the difference between the phase of the reference signal and the microwave is taken from terminal 7. Put it out.

[Problem that the invention attempts to solve]

However, this conventional configuration had the following problems, so the sampling phase detector was monolithically mounted on a gallium arsenide substrate.

Therefore, it was difficult to make it into an integrated circuit.

■ A silicon step recovery diode is required. Currently, only silicon is used as a material for step recovery diodes; gallium arsenide is not used.

■ A transformer is required. The control signal requires the use of a transformer to generate two positive and negative pulses. In the case of only positive or only negative pulses, the control signal's peak appears in the output.

(2) In order to fully operate the step and pre-recovery diodes, the input power of the reference signal must be large, on the order of tens to hundreds of mW. Such large input power creates a heat source) and is unsuitable for integrated circuit implementation.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a sampling phase detector that can be monolithically integrated on a gallium arsenide substrate.

[Next means and actions to solve the problem]

In order to achieve the above object, the sampling phase detector of the present invention converts a low-frequency sine wave signal into a narrow and sharp pulse by using an amplitude limiting circuit, a delay circuit, and an AND r -). It is characterized by sampling microwaves by switching all field effect transistors as a control signal. This has the following characteristics.

(2) Amplitude limiting circuits, delay circuits, AND gates, and field effect transistors for switching can all be constructed of gallium arsenide.

■ The switching control signal is input to the gate of the field effect transistor. At this time, since no current flows between the gate and source or between the gate and drain, no peak of the control signal appears in the output.

(2) When the amplitude limiting circuit is configured using field effect transistors, the input power can be extremely small, on the order of nanowatts, by inputting the reference signal to the gate of the field effect transistor.

〔Example〕

FIG. 1 shows one embodiment of the present invention.

FET is a field effect transistor, vDD is a drain bias power supply, vGO is a gate bias power supply, CB is a high frequency bypass capacitor, cc is a coupling capacitor, R is a high resistance to keep the field effect transistor ff-) at ground potential, R1 is the goo of field effect transistor 4)
The high resistance R2 for keeping the potential at iV, , is a high resistance for keeping the source of the field effect transistor 4 at the ground potential. The nine sections A to D surrounded by the broken line are each a single-stage amplifier circuit, and the section E surrounded by the broken line is an ANDf-1.

The operation of this circuit fc will be explained with reference to FIG.

When a sine wave reference signal having a frequency of, for example, 250 MHz is input to the input terminal IN1, it is saturated by the two-stage amplifier circuits A and B, and the rising edge becomes sharp. Here, the entire amplitude limiting circuit that converts a sine wave signal into a square wave signal is constructed by connecting amplifier circuits in multiple stages. This output signal (Fig. 2 ■) is input to AND gate No. 11. Also, the ratio signal passing through the amplifier circuit A) C-+D is delayed from the signal shown in Fig. 2 ■. It becomes like this. This signal is input to AND gate E at number 12. As a result.

It can be obtained from number 13 of the narrow and sharp armpit wokoma gate E as shown in Figure 2 (■). The frequency of this noise is 250 MEtz. This No9rus is a power supply v0
By appropriately selecting the value of .degree., it is possible to pass the entire threshold voltage v of the field effect transistor. This is input to the gate of the field effect transistor 14. A microwave input terminal N2 is provided at the drain of the field effect transistor 14, and the input terminal N2 is inputted from here as shown in FIG.
The microwave is sampled as shown in FIG. 2 by the switching operation using the pulses described above.

A phase detection output obtained by integrating this by a capacitor 15 is taken out from an output terminal OUT.

With the above configuration, the sampling phase detector does not require a transformer or a step recovery diode.

〔Effect of the invention〕

As explained above, according to the present invention, the entire circuit is monolithically integrated on a gallium arsenide substrate in order to sample microwaves with a reference signal of about nanowatts without using any transformers, steppers, or pre-recovery diodes. It becomes possible to

This is effective for downsizing the phase-locked 8-oscillation circuit.

[Brief explanation of the drawing]

Figure 11 shows the components of an embodiment of the sampling phase detector of the present invention, Figure 2 is a signal waveform diagram for explaining the circuit in Figure 1, and Figure 3 is a circuit showing a conventional sampling phase detector. It is a diagram. FET: Field effect transistor, IN,: Sine wave reference signal input terminal, IN2: Microwave input terminal, OUT
: Phase detection output terminal s VDD Power supply for Nidrain bias, Vog : Type source for boot bias, Cs: High frequency bypass capacitor, Cc: Coupling capacitor, R: High resistance to keep the gate at ground potential, R4: Field effect transistor V the gate of J4. . R2: High resistance to keep the source of the field effect transistor 14 at ground potential. Diagram

Claims (1)

[Claims] Equipped with an amplitude limiting circuit, a delay circuit, an AND gate, and a field effect transistor, a sine wave reference signal is input to the input terminal of the amplitude limiting circuit, and the output of the amplitude limiting circuit is branched into two, one of which is connected to the AND gate. The output of the delay circuit is input to the other terminal of the AND gate, the output of the AND gate is input to the gate of the field effect transistor, and the output of the AND gate is input to either the drain or the source. A sampling phase detector characterized in that a microwave is inputted and a voltage corresponding to a phase difference between a reference signal and a microwave signal is extracted from the other side.